1. Field of the Invention
This invention relates to the incineration of waste gas and, in one aspect, to systems and methods for incinerating vented waste gas containing oxygen, nitrogen and volatile organic waste.
2. Description of Related Art
The prior art discloses a variety of systems used for incinerating waste gasses. These include: regenerative vent incinerators; large main burner incinerators; and catalytic converters.
In certain large main burner incinerators and multiple burner incinerators enough fuel and air must be provided to the burner to heat contaminated or vitiated waste gas streams so that volatile organic waste therein is destroyed, e.g. at a required temperature of about 1700 degrees Fahrenheit. Such systems require a relatively large amount of fuel and of combustion air, a relatively large volume combustion chamber, and relatively large flue gas cleaning equipment. Regenerative waste gas ("vents") incinerators are relatively expensive; have a relatively low destruction efficiency of waste organic; are mechanically complex; and have a comparatively low turndown (i.e. percent of rated capacity, e.g. 85% to 100%) based on fuel value of waste gases. Catalytic converters are relatively expensive. Catalysts used therein are subject to poisoning rendering them inefficient or ineffective. Low turndown and lack of temperature control of a catalyst bed may present problems such as damage to equipment, low efficiency, corrosion of equipment, and the level of organic destruction may be relatively low.
Some prior art waste gas incinerators employ contaminated air for combustion air in a main burner, resulting in unstable flames if waste gas low in oxygen is being incinerated. If fuel value of the contaminants varies, control and safety problems result such as flameout or flashing back into a vent header. Such a burner is usually being fired in a fuel-starved or fuel-rich condition, creating further stability problems.
There has long been a need for methods and systems for efficiently and effectively incinerating waste gasses. There has long been a need for such methods and systems which can be run for long periods of time in a stable manner. There has long been a need for such methods and systems which do not require large main burners and which provide an acceptable level of destruction of organic wastes. There has long been a need for simple solutions to these problems which can be effected at relatively low cost. There has long been a need for such methods and systems which do not rely on catalysts, particularly catalysts which can be poisoned.